The lake was originally known as
Lake Pithlachocco. It was renamed after
Daniel Newnan, who led a detachment of Georgia militia that fought an inconclusive battle with
Seminoles near the lake in 1812. Prairie Creek, the principal outlet of Newnans Lake, originally drained into
Paynes Prairie. The Camp family, which owned Paynes Prairie and operated a cattle ranch on it, wanted to drain the prairie to improve it as pasture. After very heavy rain flooded the Prairie in 1927, the Camps commenced projects to lower the water table on the Prairie that included diverting Prairie Creek to the River Styx, which flows into
Orange Lake. In the Spring and Summer of 2000, a drought revealed canoe remnants. Fifty-five of the canoes were analyzed through radiocarbon assays, which showed 41 of them to date to between 2300 and 5000 B.C. The wood choice and manufacturing techniques were comparable to other Archaic Period canoes. The discovery led to the
site's addition to the National Register of Historic Places in March 2001. ==Hydrology==